The steel industry recognises the importance of the issues surrounding emissions to air and their impact on ambient air quality, human health and the environment.

For decades, the steel industry has taken measures to address these issues, thereby significantly and demonstrably reducing emissions per tonne of steel.

Steel, whether produced via the blast furnace route or the electric arc furnace route requires the transport, storage, handling, heating and transformation of large amounts of raw materials. All these processes have the potential to generate emissions to air *, primarily in the form of dust/particulate matter (PM), sulphur dioxide (SO2) and nitrous oxides (NOx). Other emissions generated in small quantities include dioxins and heavy metals, typically attached to dust particles.

Today, all steel plants are subject to environmental regulation, which set requirements to restrict emissions to air. This regulatory framework is translated into an environmental permit (or licence to operate), which establishes plant-specific Emission Limit Values (ELVs) covering the primary emissions to air, dust, SO2, and NOx, and in most cases other emissions.

The environmental permit also sets monitoring requirements and it is common for steel plants to have additional requirements within the permit, such as maximum production capacity, emission ceilings for specific emissions, taxes or fees on emissions or specific reduction targets.

* Emissions to air have the particularity of having a local or regional reach as opposed to CO2 emissions, which have a global impact, and are therefore not covered in this report.

Fabric dust filters in steel plants typically have a collection efficiency of more than 99% even when particle size is very small. thyssenkrupp

Source: UNECE Convention on long-range transboundary air pollution

Key points from this report

Legislation must be technology neutral allowing air quality requirements to be met with technologies/practices of choice.

Air quality regulations must be based on sound science and be achievable.

Collaboration between all stakeholders is key to respond to any emerging health and environmental issue.

Monitoring methods and highly sophisticated modelling systems are key to selecting the most efficient air quality improvement measures.

Emissions from stacks versus diffuse and fugitive sources

Environmental permits and ELVs must be based on sound science with respect to the potential risk to human health and the environment, and they need to be achievable.
A mix of natural and man-made emissions contribute to air quality. Highly sophisticated methods are required to identify the source of the emissions.

Emissions management practices